// Copyright 2009-2012 by contributors, MIT License
// vim: ts=4 sts=4 sw=4 expandtab

// Module systems magic dance
(function(definition) {
	// RequireJS
	if (typeof define == "function") {
		define(definition);
		// YUI3
	} else if (typeof YUI == "function") {
		YUI.add("es5", definition);
		// CommonJS and <script>
	} else {
		definition();
	}
})(function() {

	/**
	 * Brings an environment as close to ECMAScript 5 compliance as is possible
	 * with the facilities of erstwhile engines.
	 * 
	 * Annotated ES5: http://es5.github.com/ (specific links below) ES5 Spec:
	 * http://www.ecma-international.org/publications/files/ECMA-ST/Ecma-262.pdf
	 * Required reading:
	 * http://javascriptweblog.wordpress.com/2011/12/05/extending-javascript-natives/
	 */

	//
	// Function
	// ========
	//
	// ES-5 15.3.4.5
	// http://es5.github.com/#x15.3.4.5
	function Empty() {
	}

	if (!Function.prototype.bind) {
		Function.prototype.bind = function bind(that) { // .length is 1
			// 1. Let Target be the this value.
			var target = this;
			// 2. If IsCallable(Target) is false, throw a TypeError exception.
			if (typeof target != "function") {
				throw new TypeError("Function.prototype.bind called on incompatible "
						+ target);
			}
			// 3. Let A be a new (possibly empty) internal list of all of the
			// argument values provided after thisArg (arg1, arg2 etc), in
			// order.
			// XXX slicedArgs will stand in for "A" if used
			var args = _Array_slice_.call(arguments, 1); // for normal call
			// 4. Let F be a new native ECMAScript object.
			// 11. Set the [[Prototype]] internal property of F to the standard
			// built-in Function prototype object as specified in 15.3.3.1.
			// 12. Set the [[Call]] internal property of F as described in
			// 15.3.4.5.1.
			// 13. Set the [[Construct]] internal property of F as described in
			// 15.3.4.5.2.
			// 14. Set the [[HasInstance]] internal property of F as described
			// in
			// 15.3.4.5.3.
			var bound = function() {

				if (this instanceof bound) {
					// 15.3.4.5.2 [[Construct]]
					// When the [[Construct]] internal method of a function
					// object,
					// F that was created using the bind function is called with
					// a
					// list of arguments ExtraArgs, the following steps are
					// taken:
					// 1. Let target be the value of F's [[TargetFunction]]
					// internal property.
					// 2. If target has no [[Construct]] internal method, a
					// TypeError exception is thrown.
					// 3. Let boundArgs be the value of F's [[BoundArgs]]
					// internal
					// property.
					// 4. Let args be a new list containing the same values as
					// the
					// list boundArgs in the same order followed by the same
					// values as the list ExtraArgs in the same order.
					// 5. Return the result of calling the [[Construct]]
					// internal
					// method of target providing args as the arguments.

					var result = target.apply(this, args.concat(_Array_slice_
									.call(arguments)));
					if (Object(result) === result) {
						return result;
					}
					return this;

				} else {
					// 15.3.4.5.1 [[Call]]
					// When the [[Call]] internal method of a function object,
					// F,
					// which was created using the bind function is called with
					// a
					// this value and a list of arguments ExtraArgs, the
					// following
					// steps are taken:
					// 1. Let boundArgs be the value of F's [[BoundArgs]]
					// internal
					// property.
					// 2. Let boundThis be the value of F's [[BoundThis]]
					// internal
					// property.
					// 3. Let target be the value of F's [[TargetFunction]]
					// internal
					// property.
					// 4. Let args be a new list containing the same values as
					// the
					// list boundArgs in the same order followed by the same
					// values as the list ExtraArgs in the same order.
					// 5. Return the result of calling the [[Call]] internal
					// method
					// of target providing boundThis as the this value and
					// providing args as the arguments.

					// equiv: target.call(this, ...boundArgs, ...args)
					return target.apply(that, args.concat(_Array_slice_
									.call(arguments)));

				}

			};
			if (target.prototype) {
				Empty.prototype = target.prototype;
				bound.prototype = new Empty();
				// Clean up dangling references.
				Empty.prototype = null;
			}
			// XXX bound.length is never writable, so don't even try
			//
			// 15. If the [[Class]] internal property of Target is "Function",
			// then
			// a. Let L be the length property of Target minus the length of A.
			// b. Set the length own property of F to either 0 or L, whichever
			// is
			// larger.
			// 16. Else set the length own property of F to 0.
			// 17. Set the attributes of the length own property of F to the
			// values
			// specified in 15.3.5.1.

			// TODO
			// 18. Set the [[Extensible]] internal property of F to true.

			// TODO
			// 19. Let thrower be the [[ThrowTypeError]] function Object
			// (13.2.3).
			// 20. Call the [[DefineOwnProperty]] internal method of F with
			// arguments "caller", PropertyDescriptor {[[Get]]: thrower,
			// [[Set]]:
			// thrower, [[Enumerable]]: false, [[Configurable]]: false}, and
			// false.
			// 21. Call the [[DefineOwnProperty]] internal method of F with
			// arguments "arguments", PropertyDescriptor {[[Get]]: thrower,
			// [[Set]]: thrower, [[Enumerable]]: false, [[Configurable]]:
			// false},
			// and false.

			// TODO
			// NOTE Function objects created using Function.prototype.bind do
			// not
			// have a prototype property or the [[Code]], [[FormalParameters]],
			// and
			// [[Scope]] internal properties.
			// XXX can't delete prototype in pure-js.

			// 22. Return F.
			return bound;
		};
	}

	// Shortcut to an often accessed properties, in order to avoid multiple
	// dereference that costs universally.
	// _Please note: Shortcuts are defined after `Function.prototype.bind` as we
	// us it in defining shortcuts.
	var call = Function.prototype.call;
	var prototypeOfArray = Array.prototype;
	var prototypeOfObject = Object.prototype;
	var _Array_slice_ = prototypeOfArray.slice;
	// Having a toString local variable name breaks in Opera so use _toString.
	var _toString = call.bind(prototypeOfObject.toString);
	var owns = call.bind(prototypeOfObject.hasOwnProperty);

	// If JS engine supports accessors creating shortcuts.
	var defineGetter;
	var defineSetter;
	var lookupGetter;
	var lookupSetter;
	var supportsAccessors;
	if ((supportsAccessors = owns(prototypeOfObject, "__defineGetter__"))) {
		defineGetter = call.bind(prototypeOfObject.__defineGetter__);
		defineSetter = call.bind(prototypeOfObject.__defineSetter__);
		lookupGetter = call.bind(prototypeOfObject.__lookupGetter__);
		lookupSetter = call.bind(prototypeOfObject.__lookupSetter__);
	}

	//
	// Array
	// =====
	//

	// ES5 15.4.4.12
	// http://es5.github.com/#x15.4.4.12
	// Default value for second param
	// [bugfix, ielt9, old browsers]
	// IE < 9 bug: [1,2].splice(0).join("") == "" but should be "12"
	if ([1, 2].splice(0).length != 2) {
		var array_splice = Array.prototype.splice;

		if (function() { // test IE < 9 to splice bug - see issue #138
			function makeArray(l) {
				var a = [];
				while (l--) {
					a.unshift(l)
				}
				return a
			}

			var array = [], lengthBefore;

			array.splice.bind(array, 0, 0).apply(null, makeArray(20));
			array.splice.bind(array, 0, 0).apply(null, makeArray(26));

			lengthBefore = array.length; // 20
			array.splice(5, 0, "XXX"); // add one element

			if (lengthBefore + 1 == array.length) {
				return true;// has right splice implementation without bugs
			}
			// else {
			// IE8 bug
			// }
		}()) {// IE 6/7
			Array.prototype.splice = function(start, deleteCount) {
				if (!arguments.length) {
					return [];
				} else {
					return array_splice.apply(this, [
									start === void 0 ? 0 : start,
									deleteCount === void 0
											? (this.length - start)
											: deleteCount].concat(_Array_slice_
									.call(arguments, 2)))
				}
			};
		} else {// IE8
			Array.prototype.splice = function(start, deleteCount) {
				var result, args = _Array_slice_.call(arguments, 2), addElementsCount = args.length;

				if (!arguments.length) {
					return [];
				}

				if (start === void 0) { // default
					start = 0;
				}
				if (deleteCount === void 0) { // default
					deleteCount = this.length - start;
				}

				if (addElementsCount > 0) {
					if (deleteCount <= 0) {
						if (start == this.length) { // tiny optimisation #1
							this.push.apply(this, args);
							return [];
						}

						if (start == 0) { // tiny optimisation #2
							this.unshift.apply(this, args);
							return [];
						}
					}

					// Array.prototype.splice implementation
					result = _Array_slice_.call(this, start, start
									+ deleteCount);// delete part
					args.push.apply(args, _Array_slice_.call(this, start
											+ deleteCount, this.length));// right
																			// part
					args.unshift
							.apply(args, _Array_slice_.call(this, 0, start));// left
																				// part

					// delete all items from this array and replace it to 'left
					// part' + _Array_slice_.call(arguments, 2) + 'right part'
					args.unshift(0, this.length);

					array_splice.apply(this, args);

					return result;
				}

				return array_splice.call(this, start, deleteCount);
			}

		}
	}

	// ES5 15.4.4.12
	// http://es5.github.com/#x15.4.4.13
	// Return len+argCount.
	// [bugfix, ielt8]
	// IE < 8 bug: [].unshift(0) == undefined but should be "1"
	if ([].unshift(0) != 1) {
		var array_unshift = Array.prototype.unshift;
		Array.prototype.unshift = function() {
			array_unshift.apply(this, arguments);
			return this.length;
		};
	}

	// ES5 15.4.3.2
	// http://es5.github.com/#x15.4.3.2
	// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/isArray
	if (!Array.isArray) {
		Array.isArray = function isArray(obj) {
			return _toString(obj) == "[object Array]";
		};
	}

	// The IsCallable() check in the Array functions
	// has been replaced with a strict check on the
	// internal class of the object to trap cases where
	// the provided function was actually a regular
	// expression literal, which in V8 and
	// JavaScriptCore is a typeof "function". Only in
	// V8 are regular expression literals permitted as
	// reduce parameters, so it is desirable in the
	// general case for the shim to match the more
	// strict and common behavior of rejecting regular
	// expressions.

	// ES5 15.4.4.18
	// http://es5.github.com/#x15.4.4.18
	// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/array/forEach

	// Check failure of by-index access of string characters (IE < 9)
	// and failure of `0 in boxedString` (Rhino)
	var boxedString = Object("a"), splitString = boxedString[0] != "a"
			|| !(0 in boxedString);

	if (!Array.prototype.forEach) {
		Array.prototype.forEach = function forEach(fun /* , thisp */) {
			var object = toObject(this), self = splitString
					&& _toString(this) == "[object String]"
					? this.split("")
					: object, thisp = arguments[1], i = -1, length = self.length >>> 0;

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(); // TODO message
			}

			while (++i < length) {
				if (i in self) {
					// Invoke the callback function with call, passing
					// arguments:
					// context, property value, property key, thisArg object
					// context
					fun.call(thisp, self[i], i, object);
				}
			}
		};
	}

	// ES5 15.4.4.19
	// http://es5.github.com/#x15.4.4.19
	// https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Objects/Array/map
	if (!Array.prototype.map) {
		Array.prototype.map = function map(fun /* , thisp */) {
			var object = toObject(this), self = splitString
					&& _toString(this) == "[object String]"
					? this.split("")
					: object, length = self.length >>> 0, result = Array(length), thisp = arguments[1];

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(fun + " is not a function");
			}

			for (var i = 0; i < length; i++) {
				if (i in self)
					result[i] = fun.call(thisp, self[i], i, object);
			}
			return result;
		};
	}

	// ES5 15.4.4.20
	// http://es5.github.com/#x15.4.4.20
	// https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Objects/Array/filter
	if (!Array.prototype.filter) {
		Array.prototype.filter = function filter(fun /* , thisp */) {
			var object = toObject(this), self = splitString
					&& _toString(this) == "[object String]"
					? this.split("")
					: object, length = self.length >>> 0, result = [], value, thisp = arguments[1];

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(fun + " is not a function");
			}

			for (var i = 0; i < length; i++) {
				if (i in self) {
					value = self[i];
					if (fun.call(thisp, value, i, object)) {
						result.push(value);
					}
				}
			}
			return result;
		};
	}

	// ES5 15.4.4.16
	// http://es5.github.com/#x15.4.4.16
	// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/every
	if (!Array.prototype.every) {
		Array.prototype.every = function every(fun /* , thisp */) {
			var object = toObject(this), self = splitString
					&& _toString(this) == "[object String]"
					? this.split("")
					: object, length = self.length >>> 0, thisp = arguments[1];

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(fun + " is not a function");
			}

			for (var i = 0; i < length; i++) {
				if (i in self && !fun.call(thisp, self[i], i, object)) {
					return false;
				}
			}
			return true;
		};
	}

	// ES5 15.4.4.17
	// http://es5.github.com/#x15.4.4.17
	// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/some
	if (!Array.prototype.some) {
		Array.prototype.some = function some(fun /* , thisp */) {
			var object = toObject(this), self = splitString
					&& _toString(this) == "[object String]"
					? this.split("")
					: object, length = self.length >>> 0, thisp = arguments[1];

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(fun + " is not a function");
			}

			for (var i = 0; i < length; i++) {
				if (i in self && fun.call(thisp, self[i], i, object)) {
					return true;
				}
			}
			return false;
		};
	}

	// ES5 15.4.4.21
	// http://es5.github.com/#x15.4.4.21
	// https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Objects/Array/reduce
	if (!Array.prototype.reduce) {
		Array.prototype.reduce = function reduce(fun /* , initial */) {
			var object = toObject(this), self = splitString
					&& _toString(this) == "[object String]"
					? this.split("")
					: object, length = self.length >>> 0;

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(fun + " is not a function");
			}

			// no value to return if no initial value and an empty array
			if (!length && arguments.length == 1) {
				throw new TypeError("reduce of empty array with no initial value");
			}

			var i = 0;
			var result;
			if (arguments.length >= 2) {
				result = arguments[1];
			} else {
				do {
					if (i in self) {
						result = self[i++];
						break;
					}

					// if array contains no values, no initial value to return
					if (++i >= length) {
						throw new TypeError("reduce of empty array with no initial value");
					}
				} while (true);
			}

			for (; i < length; i++) {
				if (i in self) {
					result = fun.call(void 0, result, self[i], i, object);
				}
			}

			return result;
		};
	}

	// ES5 15.4.4.22
	// http://es5.github.com/#x15.4.4.22
	// https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Objects/Array/reduceRight
	if (!Array.prototype.reduceRight) {
		Array.prototype.reduceRight = function reduceRight(fun /* , initial */) {
			var object = toObject(this), self = splitString
					&& _toString(this) == "[object String]"
					? this.split("")
					: object, length = self.length >>> 0;

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(fun + " is not a function");
			}

			// no value to return if no initial value, empty array
			if (!length && arguments.length == 1) {
				throw new TypeError("reduceRight of empty array with no initial value");
			}

			var result, i = length - 1;
			if (arguments.length >= 2) {
				result = arguments[1];
			} else {
				do {
					if (i in self) {
						result = self[i--];
						break;
					}

					// if array contains no values, no initial value to return
					if (--i < 0) {
						throw new TypeError("reduceRight of empty array with no initial value");
					}
				} while (true);
			}

			if (i < 0) {
				return result;
			}

			do {
				if (i in this) {
					result = fun.call(void 0, result, self[i], i, object);
				}
			} while (i--);

			return result;
		};
	}

	// ES5 15.4.4.14
	// http://es5.github.com/#x15.4.4.14
	// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/indexOf
	if (!Array.prototype.indexOf || ([0, 1].indexOf(1, 2) != -1)) {
		Array.prototype.indexOf = function indexOf(sought /* , fromIndex */) {
			var self = splitString && _toString(this) == "[object String]"
					? this.split("")
					: toObject(this), length = self.length >>> 0;

			if (!length) {
				return -1;
			}

			var i = 0;
			if (arguments.length > 1) {
				i = toInteger(arguments[1]);
			}

			// handle negative indices
			i = i >= 0 ? i : Math.max(0, length + i);
			for (; i < length; i++) {
				if (i in self && self[i] === sought) {
					return i;
				}
			}
			return -1;
		};
	}

	// ES5 15.4.4.15
	// http://es5.github.com/#x15.4.4.15
	// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/lastIndexOf
	if (!Array.prototype.lastIndexOf || ([0, 1].lastIndexOf(0, -3) != -1)) {
		Array.prototype.lastIndexOf = function lastIndexOf(sought /*
																	 * ,
																	 * fromIndex
																	 */) {
			var self = splitString && _toString(this) == "[object String]"
					? this.split("")
					: toObject(this), length = self.length >>> 0;

			if (!length) {
				return -1;
			}
			var i = length - 1;
			if (arguments.length > 1) {
				i = Math.min(i, toInteger(arguments[1]));
			}
			// handle negative indices
			i = i >= 0 ? i : length - Math.abs(i);
			for (; i >= 0; i--) {
				if (i in self && sought === self[i]) {
					return i;
				}
			}
			return -1;
		};
	}

	//
	// Object
	// ======
	//

	// ES5 15.2.3.14
	// http://es5.github.com/#x15.2.3.14
	if (!Object.keys) {
		// http://whattheheadsaid.com/2010/10/a-safer-object-keys-compatibility-implementation
		var hasDontEnumBug = true, dontEnums = ["toString", "toLocaleString",
				"valueOf", "hasOwnProperty", "isPrototypeOf",
				"propertyIsEnumerable", "constructor"], dontEnumsLength = dontEnums.length;

		for (var key in {
			"toString" : null
		}) {
			hasDontEnumBug = false;
		}

		Object.keys = function keys(object) {

			if ((typeof object != "object" && typeof object != "function")
					|| object === null) {
				throw new TypeError("Object.keys called on a non-object");
			}

			var keys = [];
			for (var name in object) {
				if (owns(object, name)) {
					keys.push(name);
				}
			}

			if (hasDontEnumBug) {
				for (var i = 0, ii = dontEnumsLength; i < ii; i++) {
					var dontEnum = dontEnums[i];
					if (owns(object, dontEnum)) {
						keys.push(dontEnum);
					}
				}
			}
			return keys;
		};

	}

	//
	// Date
	// ====
	//

	// ES5 15.9.5.43
	// http://es5.github.com/#x15.9.5.43
	// This function returns a String value represent the instance in time
	// represented by this Date object. The format of the String is the Date
	// Time
	// string format defined in 15.9.1.15. All fields are present in the String.
	// The time zone is always UTC, denoted by the suffix Z. If the time value
	// of
	// this object is not a finite Number a RangeError exception is thrown.
	var negativeDate = -62198755200000, negativeYearString = "-000001";
	if (!Date.prototype.toISOString
			|| (new Date(negativeDate).toISOString()
					.indexOf(negativeYearString) === -1)) {
		Date.prototype.toISOString = function toISOString() {
			var result, length, value, year, month;
			if (!isFinite(this)) {
				throw new RangeError("Date.prototype.toISOString called on non-finite value.");
			}

			year = this.getUTCFullYear();

			month = this.getUTCMonth();
			// see https://github.com/kriskowal/es5-shim/issues/111
			year += Math.floor(month / 12);
			month = (month % 12 + 12) % 12;

			// the date time string format is specified in 15.9.1.15.
			result = [month + 1, this.getUTCDate(), this.getUTCHours(),
					this.getUTCMinutes(), this.getUTCSeconds()];
			year = ((year < 0 ? "-" : (year > 9999 ? "+" : "")) + ("00000" + Math
					.abs(year)).slice(0 <= year && year <= 9999 ? -4 : -6));

			length = result.length;
			while (length--) {
				value = result[length];
				// pad months, days, hours, minutes, and seconds to have two
				// digits.
				if (value < 10) {
					result[length] = "0" + value;
				}
			}
			// pad milliseconds to have three digits.
			return (year + "-" + result.slice(0, 2).join("-") + "T"
					+ result.slice(2).join(":") + "."
					+ ("000" + this.getUTCMilliseconds()).slice(-3) + "Z");
		};
	}

	// ES5 15.9.5.44
	// http://es5.github.com/#x15.9.5.44
	// This function provides a String representation of a Date object for use
	// by
	// JSON.stringify (15.12.3).
	var dateToJSONIsSupported = false;
	try {
		dateToJSONIsSupported = (Date.prototype.toJSON
				&& new Date(NaN).toJSON() === null
				&& new Date(negativeDate).toJSON().indexOf(negativeYearString) !== -1 && Date.prototype.toJSON
				.call({ // generic
					toISOString : function() {
						return true;
					}
				}));
	} catch (e) {
	}
	if (!dateToJSONIsSupported) {
		Date.prototype.toJSON = function toJSON(key) {
			// When the toJSON method is called with argument key, the following
			// steps are taken:

			// 1. Let O be the result of calling ToObject, giving it the this
			// value as its argument.
			// 2. Let tv be toPrimitive(O, hint Number).
			var o = Object(this), tv = toPrimitive(o), toISO;
			// 3. If tv is a Number and is not finite, return null.
			if (typeof tv === "number" && !isFinite(tv)) {
				return null;
			}
			// 4. Let toISO be the result of calling the [[Get]] internal method
			// of
			// O with argument "toISOString".
			toISO = o.toISOString;
			// 5. If IsCallable(toISO) is false, throw a TypeError exception.
			if (typeof toISO != "function") {
				throw new TypeError("toISOString property is not callable");
			}
			// 6. Return the result of calling the [[Call]] internal method of
			// toISO with O as the this value and an empty argument list.
			return toISO.call(o);

			// NOTE 1 The argument is ignored.

			// NOTE 2 The toJSON function is intentionally generic; it does not
			// require that its this value be a Date object. Therefore, it can
			// be
			// transferred to other kinds of objects for use as a method.
			// However,
			// it does require that any such object have a toISOString method.
			// An
			// object is free to use the argument key to filter its
			// stringification.
		};
	}

	// ES5 15.9.4.2
	// http://es5.github.com/#x15.9.4.2
	// based on work shared by Daniel Friesen (dantman)
	// http://gist.github.com/303249
	if (!Date.parse || "Date.parse is buggy") {
		// XXX global assignment won't work in embeddings that use
		// an alternate object for the context.
		Date = (function(NativeDate) {

			// Date.length === 7
			function Date(Y, M, D, h, m, s, ms) {
				var length = arguments.length;
				if (this instanceof NativeDate) {
					var date = length == 1 && String(Y) === Y ? // isString(Y)
							// We explicitly pass it through parse:
							new NativeDate(Date.parse(Y))
							:
							// We have to manually make calls depending on
							// argument
							// length here
							length >= 7
									? new NativeDate(Y, M, D, h, m, s, ms)
									: length >= 6
											? new NativeDate(Y, M, D, h, m, s)
											: length >= 5
													? new NativeDate(Y, M, D,
															h, m)
													: length >= 4
															? new NativeDate(Y,
																	M, D, h)
															: length >= 3
																	? new NativeDate(
																			Y,
																			M,
																			D)
																	: length >= 2
																			? new NativeDate(
																					Y,
																					M)
																			: length >= 1
																					? new NativeDate(Y)
																					: new NativeDate();
					// Prevent mixups with unfixed Date object
					date.constructor = Date;
					return date;
				}
				return NativeDate.apply(this, arguments);
			};

			// 15.9.1.15 Date Time String Format.
			var isoDateExpression = new RegExp("^" + "(\\d{4}|[\+\-]\\d{6})" + // four-digit
																				// year
																				// capture
																				// or
																				// sign
																				// +
					// 6-digit extended year
					"(?:-(\\d{2})" + // optional month capture
					"(?:-(\\d{2})" + // optional day capture
					"(?:" + // capture hours:minutes:seconds.milliseconds
					"T(\\d{2})" + // hours capture
					":(\\d{2})" + // minutes capture
					"(?:" + // optional :seconds.milliseconds
					":(\\d{2})" + // seconds capture
					"(?:(\\.\\d{1,}))?" + // milliseconds capture
					")?" + "(" + // capture UTC offset component
					"Z|" + // UTC capture
					"(?:" + // offset specifier +/-hours:minutes
					"([-+])" + // sign capture
					"(\\d{2})" + // hours offset capture
					":(\\d{2})" + // minutes offset capture
					")" + ")?)?)?)?" + "$");

			var months = [0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304,
					334, 365];

			function dayFromMonth(year, month) {
				var t = month > 1 ? 1 : 0;
				return (months[month] + Math.floor((year - 1969 + t) / 4)
						- Math.floor((year - 1901 + t) / 100)
						+ Math.floor((year - 1601 + t) / 400) + 365
						* (year - 1970));
			}

			// Copy any custom methods a 3rd party library may have added
			for (var key in NativeDate) {
				Date[key] = NativeDate[key];
			}

			// Copy "native" methods explicitly; they may be non-enumerable
			Date.now = NativeDate.now;
			Date.UTC = NativeDate.UTC;
			Date.prototype = NativeDate.prototype;
			Date.prototype.constructor = Date;

			// Upgrade Date.parse to handle simplified ISO 8601 strings
			Date.parse = function parse(string) {
				var match = isoDateExpression.exec(string);
				if (match) {
					// parse months, days, hours, minutes, seconds, and
					// milliseconds
					// provide default values if necessary
					// parse the UTC offset component
					var year = Number(match[1]), month = Number(match[2] || 1)
							- 1, day = Number(match[3] || 1) - 1, hour = Number(match[4]
							|| 0), minute = Number(match[5] || 0), second = Number(match[6]
							|| 0), millisecond = Math.floor(Number(match[7]
							|| 0)
							* 1000),
					// When time zone is missed, local offset should be used
					// (ES 5.1 bug)
					// see https://bugs.ecmascript.org/show_bug.cgi?id=112
					offset = !match[4] || match[8] ? 0 : Number(new NativeDate(
							1970, 0)), signOffset = match[9] === "-" ? 1 : -1, hourOffset = Number(match[10]
							|| 0), minuteOffset = Number(match[11] || 0), result;
					if (hour < (minute > 0 || second > 0 || millisecond > 0
							? 24
							: 25)
							&& minute < 60
							&& second < 60
							&& millisecond < 1000
							&& month > -1
							&& month < 12
							&& hourOffset < 24
							&& minuteOffset < 60
							&& // detect invalid offsets
							day > -1
							&& day < (dayFromMonth(year, month + 1) - dayFromMonth(
									year, month))) {
						result = ((dayFromMonth(year, month) + day) * 24 + hour + hourOffset
								* signOffset)
								* 60;
						result = ((result + minute + minuteOffset * signOffset)
								* 60 + second)
								* 1000 + millisecond + offset;
						if (-8.64e15 <= result && result <= 8.64e15) {
							return result;
						}
					}
					return NaN;
				}
				return NativeDate.parse.apply(this, arguments);
			};

			return Date;
		})(Date);
	}

	// ES5 15.9.4.4
	// http://es5.github.com/#x15.9.4.4
	if (!Date.now) {
		Date.now = function now() {
			return new Date().getTime();
		};
	}

	//
	// Number
	// ======
	//

	// ES5.1 15.7.4.5
	// http://es5.github.com/#x15.7.4.5
	if (!Number.prototype.toFixed || (0.00008).toFixed(3) !== '0.000'
			|| (0.9).toFixed(0) === '0' || (1.255).toFixed(2) !== '1.25'
			|| (1000000000000000128).toFixed(0) !== "1000000000000000128") {
		// Hide these variables and functions
		(function() {
			var base, size, data, i;

			base = 1e7;
			size = 6;
			data = [0, 0, 0, 0, 0, 0];

			function multiply(n, c) {
				var i = -1;
				while (++i < size) {
					c += n * data[i];
					data[i] = c % base;
					c = Math.floor(c / base);
				}
			}

			function divide(n) {
				var i = size, c = 0;
				while (--i >= 0) {
					c += data[i];
					data[i] = Math.floor(c / n);
					c = (c % n) * base;
				}
			}

			function toString() {
				var i = size;
				var s = '';
				while (--i >= 0) {
					if (s !== '' || i === 0 || data[i] !== 0) {
						var t = String(data[i]);
						if (s === '') {
							s = t;
						} else {
							s += '0000000'.slice(0, 7 - t.length) + t;
						}
					}
				}
				return s;
			}

			function pow(x, n, acc) {
				return (n === 0 ? acc : (n % 2 === 1
						? pow(x, n - 1, acc * x)
						: pow(x * x, n / 2, acc)));
			}

			function log(x) {
				var n = 0;
				while (x >= 4096) {
					n += 12;
					x /= 4096;
				}
				while (x >= 2) {
					n += 1;
					x /= 2;
				}
				return n;
			}

			Number.prototype.toFixed = function(fractionDigits) {
				var f, x, s, m, e, z, j, k;

				// Test for NaN and round fractionDigits down
				f = Number(fractionDigits);
				f = f !== f ? 0 : Math.floor(f);

				if (f < 0 || f > 20) {
					throw new RangeError("Number.toFixed called with invalid number of decimals");
				}

				x = Number(this);

				// Test for NaN
				if (x !== x) {
					return "NaN";
				}

				// If it is too big or small, return the string value of the
				// number
				if (x <= -1e21 || x >= 1e21) {
					return String(x);
				}

				s = "";

				if (x < 0) {
					s = "-";
					x = -x;
				}

				m = "0";

				if (x > 1e-21) {
					// 1e-21 < x < 1e21
					// -70 < log2(x) < 70
					e = log(x * pow(2, 69, 1)) - 69;
					z = (e < 0 ? x * pow(2, -e, 1) : x / pow(2, e, 1));
					z *= 0x10000000000000; // Math.pow(2, 52);
					e = 52 - e;

					// -18 < e < 122
					// x = z / 2 ^ e
					if (e > 0) {
						multiply(0, z);
						j = f;

						while (j >= 7) {
							multiply(1e7, 0);
							j -= 7;
						}

						multiply(pow(10, j, 1), 0);
						j = e - 1;

						while (j >= 23) {
							divide(1 << 23);
							j -= 23;
						}

						divide(1 << j);
						multiply(1, 1);
						divide(2);
						m = toString();
					} else {
						multiply(0, z);
						multiply(1 << (-e), 0);
						m = toString()
								+ '0.00000000000000000000'.slice(2, 2 + f);
					}
				}

				if (f > 0) {
					k = m.length;

					if (k <= f) {
						m = s + '0.0000000000000000000'.slice(0, f - k + 2) + m;
					} else {
						m = s + m.slice(0, k - f) + '.' + m.slice(k - f);
					}
				} else {
					m = s + m;
				}

				return m;
			}
		}());
	}

	//
	// String
	// ======
	//

	// ES5 15.5.4.14
	// http://es5.github.com/#x15.5.4.14

	// [bugfix, IE lt 9, firefox 4, Konqueror, Opera, obscure browsers]
	// Many browsers do not split properly with regular expressions or they
	// do not perform the split correctly under obscure conditions.
	// See http://blog.stevenlevithan.com/archives/cross-browser-split
	// I've tested in many browsers and this seems to cover the deviant ones:
	// 'ab'.split(/(?:ab)*/) should be ["", ""], not [""]
	// '.'.split(/(.?)(.?)/) should be ["", ".", "", ""], not ["", ""]
	// 'tesst'.split(/(s)*/) should be ["t", undefined, "e", "s", "t"], not
	// [undefined, "t", undefined, "e", ...]
	// ''.split(/.?/) should be [], not [""]
	// '.'.split(/()()/) should be ["."], not ["", "", "."]

	var string_split = String.prototype.split;
	if ('ab'.split(/(?:ab)*/).length !== 2
			|| '.'.split(/(.?)(.?)/).length !== 4
			|| 'tesst'.split(/(s)*/)[1] === "t" || ''.split(/.?/).length === 0
			|| '.'.split(/()()/).length > 1) {
		(function() {
			var compliantExecNpcg = /()??/.exec("")[1] === void 0; // NPCG:
																	// nonparticipating
																	// capturing
																	// group

			String.prototype.split = function(separator, limit) {
				var string = this;
				if (separator === void 0 && limit === 0)
					return [];

				// If `separator` is not a regex, use native split
				if (Object.prototype.toString.call(separator) !== "[object RegExp]") {
					return string_split.apply(this, arguments);
				}

				var output = [], flags = (separator.ignoreCase ? "i" : "")
						+ (separator.multiline ? "m" : "")
						+ (separator.extended ? "x" : "") + // Proposed for ES6
						(separator.sticky ? "y" : ""), // Firefox 3+
				lastLastIndex = 0,
				// Make `global` and avoid `lastIndex` issues by working with a
				// copy
				separator = new RegExp(separator.source, flags + "g"), separator2, match, lastIndex, lastLength;
				string += ""; // Type-convert
				if (!compliantExecNpcg) {
					// Doesn't need flags gy, but they don't hurt
					separator2 = new RegExp(
							"^" + separator.source + "$(?!\\s)", flags);
				}
				/*
				 * Values for `limit`, per the spec: If undefined: 4294967295 //
				 * Math.pow(2, 32) - 1 If 0, Infinity, or NaN: 0 If positive
				 * number: limit = Math.floor(limit); if (limit > 4294967295)
				 * limit -= 4294967296; If negative number: 4294967296 -
				 * Math.floor(Math.abs(limit)) If other: Type-convert, then use
				 * the above rules
				 */
				limit = limit === void 0 ? -1 >>> 0 : // Math.pow(2, 32) - 1
						limit >>> 0; // ToUint32(limit)
				while (match = separator.exec(string)) {
					// `separator.lastIndex` is not reliable cross-browser
					lastIndex = match.index + match[0].length;
					if (lastIndex > lastLastIndex) {
						output.push(string.slice(lastLastIndex, match.index));
						// Fix browsers whose `exec` methods don't consistently
						// return `undefined` for
						// nonparticipating capturing groups
						if (!compliantExecNpcg && match.length > 1) {
							match[0].replace(separator2, function() {
										for (var i = 1; i < arguments.length
												- 2; i++) {
											if (arguments[i] === void 0) {
												match[i] = void 0;
											}
										}
									});
						}
						if (match.length > 1 && match.index < string.length) {
							Array.prototype.push.apply(output, match.slice(1));
						}
						lastLength = match[0].length;
						lastLastIndex = lastIndex;
						if (output.length >= limit) {
							break;
						}
					}
					if (separator.lastIndex === match.index) {
						separator.lastIndex++; // Avoid an infinite loop
					}
				}
				if (lastLastIndex === string.length) {
					if (lastLength || !separator.test("")) {
						output.push("");
					}
				} else {
					output.push(string.slice(lastLastIndex));
				}
				return output.length > limit ? output.slice(0, limit) : output;
			};
		}());

		// [bugfix, chrome]
		// If separator is undefined, then the result array contains just one
		// String,
		// which is the this value (converted to a String). If limit is not
		// undefined,
		// then the output array is truncated so that it contains no more than
		// limit
		// elements.
		// "0".split(undefined, 0) -> []
	} else if ("0".split(void 0, 0).length) {
		String.prototype.split = function(separator, limit) {
			if (separator === void 0 && limit === 0)
				return [];
			return string_split.apply(this, arguments);
		}
	}

	// ECMA-262, 3rd B.2.3
	// Note an ECMAScript standart, although ECMAScript 3rd Edition has a
	// non-normative section suggesting uniform semantics and it should be
	// normalized across all browsers
	// [bugfix, IE lt 9] IE < 9 substr() with negative value not working in IE
	if ("".substr && "0b".substr(-1) !== "b") {
		var string_substr = String.prototype.substr;
		/**
		 * Get the substring of a string
		 * 
		 * @param {integer}
		 *            start where to start the substring
		 * @param {integer}
		 *            length how many characters to return
		 * @return {string}
		 */
		String.prototype.substr = function(start, length) {
			return string_substr.call(this, start < 0 ? ((start = this.length
							+ start) < 0 ? 0 : start) : start, length);
		}
	}

	// ES5 15.5.4.20
	// http://es5.github.com/#x15.5.4.20
	var ws = "\x09\x0A\x0B\x0C\x0D\x20\xA0\u1680\u180E\u2000\u2001\u2002\u2003"
			+ "\u2004\u2005\u2006\u2007\u2008\u2009\u200A\u202F\u205F\u3000\u2028"
			+ "\u2029\uFEFF";
	if (!String.prototype.trim || ws.trim()) {
		// http://blog.stevenlevithan.com/archives/faster-trim-javascript
		// http://perfectionkills.com/whitespace-deviations/
		ws = "[" + ws + "]";
		var trimBeginRegexp = new RegExp("^" + ws + ws + "*"), trimEndRegexp = new RegExp(ws
				+ ws + "*$");
		String.prototype.trim = function trim() {
			if (this === void 0 || this === null) {
				throw new TypeError("can't convert " + this + " to object");
			}
			return String(this).replace(trimBeginRegexp, "").replace(
					trimEndRegexp, "");
		};
	}

	//
	// Util
	// ======
	//

	// ES5 9.4
	// http://es5.github.com/#x9.4
	// http://jsperf.com/to-integer

	function toInteger(n) {
		n = +n;
		if (n !== n) { // isNaN
			n = 0;
		} else if (n !== 0 && n !== (1 / 0) && n !== -(1 / 0)) {
			n = (n > 0 || -1) * Math.floor(Math.abs(n));
		}
		return n;
	}

	function isPrimitive(input) {
		var type = typeof input;
		return (input === null || type === "undefined" || type === "boolean"
				|| type === "number" || type === "string");
	}

	function toPrimitive(input) {
		var val, valueOf, toString;
		if (isPrimitive(input)) {
			return input;
		}
		valueOf = input.valueOf;
		if (typeof valueOf === "function") {
			val = valueOf.call(input);
			if (isPrimitive(val)) {
				return val;
			}
		}
		toString = input.toString;
		if (typeof toString === "function") {
			val = toString.call(input);
			if (isPrimitive(val)) {
				return val;
			}
		}
		throw new TypeError();
	}

	// ES5 9.9
	// http://es5.github.com/#x9.9
	var toObject = function(o) {
		if (o == null) { // this matches both null and undefined
			throw new TypeError("can't convert " + o + " to object");
		}
		return Object(o);
	};

});
